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Background Identification of biomarkers associated with immune-mediated diseases in 22q11.2 deletion syndrome is an evolving field. Objectives We sought to use a carefully phenotyped cohort to study immune parameters associated with autoimmunity and atopy in 22q11.2 deletion syndrome to define biomarkers associated with immune-mediated disease in this syndrome. Methods Chart review validated autoimmune disease and atopic condition diagnoses. Laboratory data were extracted for each subcohort and plotted according to age. A random-effects model was used to define statistical significance. Results CD19, CD4, and CD4/45RA lymphocyte populations were not different from the general cohort for patients with atopic conditions. CD4/45RA T cells were significantly lower in the subjects with immune thrombocytopenia compared with the general cohort, and CD4 T-cell counts were lower in patients with autoimmune thyroid disease. Conclusions The mechanisms of autoimmunity in cytopenias may be distinct from those of solid-organ autoimmunity in 22q11.2 deletion syndrome. This study identifies potential biomarkers for risk stratification among commonly obtained laboratory studies.

Background: Onset of type 2 diabetes (T2D) in youth confers a high risk of early adverse cardiovascular outcomes. We describe the cumulative incidence of hypertension, LDL-cholesterol dyslipidemia, hypertriglyceridemia, and prevalence of smoking over time, and examine the relationships with body mass index and measures of glycemia, insulin sensitivity, and beta-cell function in an adolescent cohort with T2D enrolled in the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study. Methods: Longitudinal data from the TODAY clinical trial and TODAY2 observational follow-up study were used to evaluate the relationships between hypertension, LDL-C dyslipidemia, hypertriglyceridemia, and smoking with risk factors using time-to-event models and generalized estimating equation models. Findings: Data were available on 677 participants. Mean age at baseline was 14±2 years and mean follow-up 10·2±4·5 years. The 14-year cumulative incidence of hypertension, LDL-C dyslipidemia, and hypertriglyceridemia was 59%, 33%, and 37% respectively, and the average prevalence of reported smoking was 23%. Male sex, non-Hispanic white race/ethnicity, obesity, poor glycemic control, lower insulin sensitivity, and reduced beta-cell function were significantly associated with an unfavorable cardiovascular risk profile. After an average of 10·2 years of follow-up, 54% of the cohort had ≥2 cardiovascular risk factors in addition to T2D. Interpretation: Cardiovascular risk factor incidence and prevalence was high over a decade of follow-up in young adults with youth-onset T2D. Addressing glucose control and insulin sensitivity, as well as medical management of cardiovascular risk factors will be critical in youth with T2D for prevention of cardiovascular morbidity and mortality. Trial Registration: Clinicaltrials.gov NCT00081328. Funding: United States National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Disease. Declaration of Interest: None of the authors reported a conflict of interest. Ethical Approval: The TODAY and TODAY2 studies were approved by institutional review boards at all 15 centers and all participants and guardians provided written informed assent and/or consent as appropriate for age.

Aims We aimed to determine the prevalence of arterial stiffness in young adults with youth-onset type 2 diabetes who previously participated in the TODAY clinical trial and whether arterial stiffness is influenced by their prior diabetes treatment assignment or glycemic control. Methods We measured arterial stiffness by femoral, radial, and foot pulse wave velocity (PWV), augmentation index (AIx), and brachial distensibility (BrachD) in 453 TODAY participants (age 20.8 ± 2.5 years, diabetes duration 7.6 ± 1.5 years, 36.4% male, BMI 36.7 ± 8.2 kg/m2) at a mean of 7.6 years post-randomization. Increased arterial stiffness in TODAY youth was defined compared with data from lean controls. We assessed whether glycemic control over time or diabetes treatment in TODAY was associated with arterial stiffness. Results Arterial stiffness was identified in up to 50% of TODAY participants. Prior diabetes treatment assignment was not associated with higher arterial stiffness. Glycemic control over time was associated with PWV radial and foot only. Age, race-ethnicity, sex, higher blood pressure and BMI were also associated with higher arterial stiffness. Conclusions Nearly half of TODAY youth have increased arterial stiffness. Targeting blood pressure and perhaps obesity and glycemic control may positively impact arterial health in adolescents with type 2 diabetes. Trial registration: ClinicalTrials.gov NCT00081328 .

Objective To compare lipoprotein profiles of prediabetic to normoglycemic obese adolescents. Study design Cross-sectional study of 95 obese, pubertal adolescents (12-17 years), who underwent oral glucose tolerance test, lipid panel, and lipoprotein subclass particle analysis (nuclear magnetic resonance spectroscopy). Univariate and linear regression analyses compared prediabetic and normoglycemic groups. Results Of 95 obese adolescents enrolled in the study, 22.1% (n = 21) had prediabetes. They were similar to normoglycemic adolescents (n = 74) in age, race, body mass index, standard lipids, total low-density lipoprotein particles (LDL-P), and total high-density lipoprotein particles (HDL-P). However, prediabetics had higher concentrations of small LDL-P (714.0 ± 288.0 vs 537.7 ± 266.5 nmol/L, P = .01) and smaller LDL-P size (20.73 ± 0.41 vs 21.18 ± 0.65 nm, P = .003), than normoglycemic youth. Prediabetics had higher small HDL-P (18.5 ± 3.8 vs 16.6 ± 3.9 umol/L, P = .046), lower large HDL-P (4.49 ± 2.0 vs 6.32 ± 2.6 umol/L, P = .004), and smaller HDL-P size (8.73 ± 0.31 vs 9.01 ± 0.39 nm, P = .003). After adjusting for demographics, Tanner stage, and body mass index using multiple linear regression, all differences remained significant except for small HDL-P. After additional adjustment for Homeostasis Model Assessment–Insulin Resistance Index, only LDL-P size difference remained significant. Conclusion Obese prediabetic adolescents have a significantly more atherogenic lipoprotein profile compared with obese normoglycemic peers. Prediabetic adolescents may benefit from more aggressive interventions to decrease future cardiovascular risk.

Objectives Data regarding atherogenic dyslipidemia and the inflammation profile in youth with type 2 diabetes is limited and the effect of insulin therapy on these variables has not previously been studied in youth. We determined the impact of insulin therapy on lipid and inflammatory markers in youth with poorly controlled type 2 diabetes. Study design In the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) multicenter trial, 285 participants failed to sustain glycemic control on randomized treatment (primary outcome, glycated hemoglobin A1c [HbA1c] at ≥8% for 6 months); 363 maintained glycemic control (never reached primary outcome). Statins were used for a low-density lipoprotein cholesterol of ≥130 mg/dL. Upon reaching the primary outcome, insulin was started. Changes in lipids and inflammatory markers (slopes over time) were examined. Results Progression of dyslipidemia was related to glycemic control. In those with the primary outcome, insulin therapy impacted HbA1c modestly, and dampened the increase in total cholesterol, low-density lipoprotein cholesterol, and total apolipoprotein B, although statin use increased from 8.6% to 22% year after the primary outcome. The increase in triglycerides and plasma nonesterified fatty acids stabilized after insulin was started, independent of HbA1c. There was an increase in high-sensitivity C-reactive protein that continued after insulin initiation, related to HbA1c and percent overweight. Conclusions Worsening dyslipidemia and inflammation over time raise concern regarding premature development of atherosclerosis in youth with type 2 diabetes. Insulin therapy has a limited benefit in the absence of glycemic control. Strategies to achieve better glycemic control are needed. Trial registration ClinicalTrials.gov : NCT00081328 .

Objective: We hypothesized that most patients with 22q11.2 deletion and a history of hypocalcemia have inadequate parathyroid function, manifested by intact parathyroid hormone levels below normal. We aimed to evaluate intact parathyroid hormone levels both during normocalcemia and at hypocalcemia, in this population. Study Design: Retrospective chart review of 103 patients with 22q11.2 deletion born since 1997 and cared for at the Children's Hospital of Philadelphia. Calcium and intact parathyroid hormone drawn simultaneously were recorded, along with clinical presentation at hypocalcemia. Results: Forty-seven simultaneous Ca/intact parathyroid hormone values were available. Seventy-nine percent of calcium levels and 81% of parathyroid hormone levels were within normal range. There were 19 patients with a history of symptomatic hypocalcemia, for whom any available simultaneous Ca/parathyroid hormone levels, before, during, or after hypocalcemia were analyzed. In this subgroup, 59% of calcium and 76% of parathyroid hormone levels were normal. None had an intact parathyroid hormone of >39.2 pg/mL at hypocalcemia. Seventy-three percent of hypocalcemic events had a precipitating stressor. Conclusions: Hypoparathyroidism in 22q11.2 deletion is mild, manifesting as a phenomenon of decreased parathyroid hormone reserve. Subjects are normocalcemic most of the time, but are unable to mount elevated intact parathyroid hormone levels, and therefore unable to correct hypocalcemia, in response to stressors.

Insulin-like growth factor binding protein-3 (IGFBP-3) is emerging as a critical regulator of cell survival. There has been no study which directly examined the potential role for this major growth factor in the programmed cell death (apoptosis) of insulin-secreting cells. To determine whether IGFBP-3 mediates apoptosis in insulin-secreting cells, we performed a rigorous series of experiments with the rat insulinoma (RIN) cell line m5F and the hamster insulin-secreting tumor (HIT) T-15. Within 24 h exogenous IGFBP-3 induced significant DNA fragmentation in RIN and HIT cells, at doses ranging from 4.4 to 2000 ng/ml (P

Hypoglycemia occurred in a 2-year-old girl with neuroblastoma. Initially, growth hormone secretion was suppressed, and she had low levels of insulin-like growth factor (IGF)-I and IGF binding protein-3, but elevated levels of large molecular weight IGF-II. We postulated that the pathogenesis of her hypoglycemia involved production of IGF-II by her neuroblastoma, leading to GH suppression and an abnormally elevated ratio of IGF to IGF binding protein. She was successfully treated with growth hormone; treatment was associated with normalization of the growth hormone-dependent growth factor levels and with euglycemia.

Dumping syndrome and postprandial hypoglycemia have been reported after Nissen fundoplication. The physiopathologic mechanisms are poorly understood and a variety of therapies have failed to control the hypoglycemia in these patients. We report a series of 6 infants with postprandial hypoglycemia after Nissen fundoplication who were treated successfully with acarbose.